Tetra hydro benzene

Catyone( l-Methyl-2-oxy 4-isopropylene-h -tetra-hydro-benzene or 6,8 p-menthadien-2 one),... 

To a stirred suspension of 3 g of methyl 2-endo-hydroxy-l-exo-hydroxymethyl-3a, 8b-cis-2,3,3a,8b-tetra hydro-1 H-5-cyclopenta[ bjbenzofuran-carboxylate in 30 ml of anhydrous tetrahydrofuran was added 1.5 ml of a solution which is obtained by dissolving 10 ml of 1,1-diethoxyethane and 200 mg of p-toluenesulfonic acid monohydrate into 10 ml of tetrahydrofuran followed by drying over molecular sieves, and the mixture was stirred for 14 hours at 60°C and then cooled. To the reaction mixture was added 100 mg of sodium hydrogen carbonate, and the mixture was stirred for 10 min at room temperature. Then, water was added to the reaction mixture and the mixture was extracted three times with ethyl acetate. The combined organic layers were washed with water and aqueous saturated solution of sodium chloride, was dried, and was concentrated to give 3.5 g of the crude crystals. The crude crystals were recrystallized from benzene-hexane to yield 2 g of the title compound (m.p. 162-163°C). 

Hydrated Naphthylamines.— We have referred to the hydrated naphthylamines in our discussion of the constitution of naphthalene (p. 772). The tetra-hydro products are of two kinds (i) Those termed aromatic in which the hydrogen is added to the benzene nucleus which does not contain the amino group and which possess the characters of aromatic amines. (2) Those termed alicyclic in which the hydrogen is added to the benzene nucleus which does contain the amino group and which possess the characters of aliphatic amines. Now while the alpha- and g/a-naphthylamines each yield both kinds of tetra-hydro products if subjected to proper treatment yet by the same treatment, viz., with sodium amalgam in amyl alcohol, the atpha-naphthylamine yields an aromatic tetra-hydro compound while the i>e/o-naphthylamine yields mostly an alicyclic compound. 

The dihalocyclopropane route is the method of choice for the synthesis of benzocyclopropenes and linearly fused cyclopropanaphthalenes, but is unsuccessful for angular cyclopropa[u]naph-thalene. Treatment of l,l-dichloro-la,2,3,7b-tetrahydro-l/f-cyclopropa[a]naphthalene(5) with potassium /ert-butoxide gave a mixture of 1-chloromethylnaphthalene, 1-terr-butoxymethyl-naphthalene and 2-terf-butoxy-l-chloromethylene-l,2,3,4-tetrahydronaphthalene, but none of the expected cyclopropa[n]naphthalene. The failure of the reaction has been attributed to difficulties in the aromatization. Isomerization of the initially produced cyclopropenyl double bond into the cyclohexane ring would require disruption of the aromatic character of the adjacent benzene nngT t-r>> 62 Similarly, attempted aromatization of l-chloro-l,2,3,7b-tetra-hydro-l//-cyclopropa[a]naphthalene (6) with 2,3-dichloro-5,6-dicyanobenzoquinone or via N-bromosuccinimide bromination followed by reaction with base afforded 4,5-benzotropone instead of cyclopropa[fl]naphthalenc. ... 

Tomboulian and Stehower5 prepared this reagent in quantitative yield by metala-tion of triphenylmethane with n-butyllithium (50-150% excess) in THF or tetra-hydro-2-methylfurane as solvent. They recommend that the n-butyllithium be prepared from lithium and n-butyl chloride in the reaction solvent. If the exchange is carried out at room temperature, excess butyllithium is rapidly consumed by reaction with tetrahydrofurane. With tetrahydropyrane as solvent, trityllithium was found to react with benzophenonc to form p-(diphenylmethyl)diphenylhydroxymethyl-benzene ... 

A sealed stainless-steel bomb containing spiro[cyclopropane-l,l -(l, 2, 3, 4 -tetra-hydro-2 -oxonaphthalene)], methylamine, CaO, and benzene rocked and heated 7 days at 100-120 3-methyl-l,2,4,5-tetrahydro-3H-benz[e]indole. Y 72.5%. F. e. s. S. L. Keely, Jr., A. J. Martinez, and F. C. Tahk, Tetrahedron 26, 4729 (1970). 

C30H28CI6O1aPus, Tetra-M Chloro-tetra-M ethyloxycarbene-di-M3-hydro-xododecacarbonyl-dichloro-hexarutheniumdl) benzene solvate, 44B, 720... 

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